​$$\text{A } 100 \text{ g block of lead is heated from } 20^\circ C \text{ to } 50^\circ C. \text{ Calculate the amount of heat transferred to the block } (\text{specific heat of lead} = 127 \text{ J} \cdot \text{kg}^{-1} \cdot K^{-1}).$$​​

Correct option is D

​$$m = 100 \text{ gm} = \frac{100}{1000} \text{ kg} = 0.1 \text{ kg}\\\Delta T = 50 - 20 \Rightarrow 30^\circ C\\C = 127 \text{ J} \cdot \text{kg}^{-1} \cdot K^{-1}\\Q = ?\\Q = mc\Delta T\\\Rightarrow 0.1 \times 127 \times 30 \Rightarrow 381 \text{ Joule}$$​​